Police had never been to Brentwood home before Monday night

Associate Attorney General Jane Young speaks during a press conference on Tuesday near the home where Brentwood police Officer Stephen Arkell was fatally shot. (JAMES A. KIMBLE/Union Leader Correspondent)

BRENTWOOD — Police officer Stephen Arkell died of multiple gunshot wounds after entering a duplex that later caught fire after a domestic dispute between a father and son, according to state investigators.

Arkell was fatally shot by 47-year-old Michael Nolan moments after he stepped inside the home at 46 Mill Pond Road in response to a domestic call reported to Brentwood police at 4:02 p.m. on Monday.

The death of Arkell, a beloved father of two, has shaken the town of Brentwood, a rural community of 4,600 where he worked as a part-time police officer for 15 years.

“I’m not sure what frame of mind he was in at the time, but Steve was a man who wanted to help people,” Brentwood police Lt. David Roy said, standing just blocks from the shooting on Tuesday. “I always considered him as a kind of peacemaker.”

Investigators with the Bureau of Alcohol, Tobacco, Firearms and Explosives and the state Fire Marshal’s Office are still trying to determine what caused the fire and explosion that eventually leveled the duplex, which was part of a 55-plus community called Mill Pond Crossing.

Propane was used for both heating and cooking inside the building, investigators said.

Many residents have been allowed back into their units, but some families remain displaced, according to Attorney General Joe Foster.

He said that victim-advocates will work with people in the community as long as necessary.

“There is much we do not know about this unspeakable tragedy,” Foster said during a news conference Tuesday.

Just before his deadly confrontation with Arkell, Nolan had been yelling at his 86-year-old father, Walter, prompting a neighbor to call Brentwood police.

“The caller indicated that they could hear the son swearing at the father, but that the argument was taking place in the house,” Associate Attorney General Jane Young said.

Brentwood police had not been called to the home before, but the caller told police that the father and son had argued in the past.

Michael Nolan and his father had no criminal record or motor vehicle records, according to investigators.

Young said Fremont police Officer Derek Franek arrived at the home to back up Arkell about four minutes later.

Franek found Walter Nolan in the front of the home and handcuffed him as a safety precaution.

“He indicated that when he went in that residence, he noticed there was a wall that had been sprayed with bullets and he saw Officer Arkell on the floor on his back,” Young said. “He walked toward him and saw that Officer Arkell had sustained what was later to be determined as a fatal injury.”

When Franek entered the house, “he was immediately met with gunfire,” Young said. “That drove him from the front of the house to the back of the house,” Young said. He was able to escape into the tree line behind the home and call for backup at approximately 4:15 p.m.

Smoke became visible from the rear of the home around 4:41 p.m. as multiple first-responders were arriving. A fire soon broke through the roof of the home.

Officers with the Seacoast Emergency Response team and the New Hampshire State Police SWAT team found Walter Nolan cuffed on the front lawn. He was treated and released at a local hospital and is currently being cared for by family.

Young said that while officers could hear shots being fired from the home, there was no exchange of gunfire between police and Michael Nolan.

The explosion happened from somewhere inside the home at about 5:49 p.m., prompting law enforcement officers and first-responders to back away from the area for safety.

Remains of Arkell and Nolan were removed from the home on Monday night.

Arkell’s body was found in the rear of the home. An autopsy performed early Tuesday concluded that Arkell, 48, died from multiple gunshot wounds. Nolan’s body was found in the garage area, along with undisclosed items that helped investigators identify him.

Young said that ATF agents and the fire marshal’s office could remain at the scene at least until Friday. She acknowledged that some evidence may not be able to be recovered because of the fire.

Foster expressed his condolences Arkell’s family and friends, saying he served with distinction.

“He put himself in harm’s way to keep others safe and he paid the ultimate sacrifice. For that we are grateful,” he said.

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